As soon as firefighters arrived, Deputy Chief Richard How said they got right to work, rescuing everyone as the smoke consumed the building.

“There were people on all parts of the fire escape being removed,” How said.

In addition to the four people in critical condition, four others are listed as serious.

Investigators said they put the fire under control by 7:27 a.m.

One firefighter suffered a minor injury.

The cause remains unknown as the investigation continues.

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